Get emergency medical help if you have any of these signs of an allergic reaction while taking omega-3 polyunsaturated fatty acids (the active ingredient contained in Lovaza) hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medication and call your doctor at once if you have any of these serious side effects:

back pain;unusual or unpleasant taste in your mouth;upset stomach, belching; ormild skin rash.This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.